To analyse, in a retrospective study, the oncological outcome, pouch-related complications, continence and micturition after radical cystoprostatectomy combined with Mainz pouch orthotopic bladder substitution to the urethra for the treatment of bladder cancer. Between 1986 and 1996, three urological departments contributed 108 male patients to the review. The same exclusion criteria from orthotopic bladder substitution were applied by all centres, i.e. multifocal or concomitant carcinoma in situ, tumour at the bladder neck, positive biopsy from the prostatic urethra, locally advanced tumour and lymph node involvement. In all, 103 patients were evaluable for follow-up, with a mean (range) follow-up of 42 (3-132) months. Pathological examination of the cystectomy specimen revealed 81% organ-confined tumours. During follow-up, 84% of patients remained free of tumour, 7% developed distant metastases, 5% local recurrences, 4% urethral recurrences, and 1% upper tract urothelial cancer; 85% of patients are capable of spontaneous voiding, with a mean pouch capacity of 720 mL. Daytime continence was achieved in 88%, including 17% wearing one safety pad; 9% had stress incontinence and 3% total incontinence; 67% could sleep through the night, with either complete continence (34%) or one safety pad (33%). Nocturnal incontinence occurred in 11%. Uretero-intestinal stenosis occurred in 15 of 205 (7%) renal units, requiring ureteric reimplantations in 11, nephrectomy in three and antegrade dilatation in one. Reflux was not noted in any patient. About half the patients were on anti-acidotic prophylaxis. The large bowel segment in the Mainz-pouch technique of orthotopic bladder substitution provides good reservoir capacity and continence rates, with less ileum used than in all-ileum pouches. The surgical technique is simple and reproducible, and in particular the antireflux ureteric implantation into the caecum protects the upper urinary tracts.